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A demonstration of the mathematical principles of the original Forth Bridge in Scotland performed at Imperial College in 1887. The central ‘weight’ is Kaichi Watanabe, one of the first Japanese engineers to study in the UK, while Sir John Fowler and Benjamin Baker provide the supports.

Long-span structural engineering illustrated. Note that weight is not the problem with this truss, but uplift is, hence the weights at the extreme ends of the truss. Tension is transferred from the exterior weights through the arms of the two men near the ends of the span, while compression struts keep this structure from collapsing under the dead weight of Mr. Watanabe. Note also that without the weight provided by Mr. Watanabe, this structure collapses (unless Messrs. Fowler and Baker scooch over and hold hands).